Children as Refrigerators: When Would Backward Altruism Appear?

Existing economic theories of the evolution of altruism between kinship members usually emphasize the role that altruism can play in facilitating coordination among kin to achieve an otherwise unachievable efficient (in terms of fitness) equilibrium. In this paper, we explore the background environment against which backward altruism was likely to appear. The instinct of sustaining one’s own life drives one to save for one’s old age. However, since social mechanisms were not sophisticated in a primitive society, the rate of return on savings was not high. As a consequence, the resources that remain for the children might be limited. Suppose a cultural menchanism or a mutation caused an individual to become backward-altruistic. She would then expect her children to adopt the same attitude as herself, and take care of her in her old age. With this expectation in mind, she would avoid inefficient savings voluntarily so that her children could obtain more resources. Thus, backward altruism in our model does not play a role of coordination, but helps parents to avoid inefficient resource disposition. We analyze the possible appearance of backward altruism as the rate of return on savings changes.

The Optimal Decoupled Liabilities: A General Analysis

The “decoupled” liability system awards the plaintiff an amount that differs from what the defendant pays. The previous approach to the optimal decoupling design is based on the assumption of complete information, which results in an optimal liability for the defendant “as much as he can afford.” This extreme conclusion may hinder the acceptability of the decoupling system. This paper proposes an alternative design based on the assumption that agents in the post-accident subgame have asymmetric information. Our model indicates that the optimal penalty faced by the defendant is generally greater than the optimal award to the plaintiff. When the potential harm is sufficiently large, the optimal penalty can be approximated by a multiple of the harm, but the plaintiff receives only a finite amount of the damages regardless of the loss suffered. Such a decoupling scheme deters frivolous lawsuits without reducing the defendants’ incentives to exercise care. Additionally, this paper derives comparative static results concerning how the trial costs of the plaintiff and defendant affect the optimal design of decoupling.

Instruments of Commerce and Knowledge: Probe Microscopy, 1980-2000

Longstanding debates about the role of the university in national culture and the global economy have entered a new phase in the past decade in most industrialized, and several industrializing, countries. One important focus of this debate is corporate involvement in academic scientific research. Proponents of the academic capitalism say that corporate involvement makes the university leaner, more agile, better able to respond to the needs of the day. Critics say that corporate involvement leaves society without the independent, critical voices traditionally lodged in universities. I argue that a science and technology studies perspective, using case studies of research communities, can push this debate in directions envisioned by neither proponents nor critics. I use the development and commercialization of the scanning tunneling microscope and the atomic force microscope as an example of how research communities continually redraw the line between corporate and academic institutions.

Transmission of Sex Preferences Across Generations: The Allocation of Educational Resources Among Siblings

The purpose of this paper is to test whether there is an intergenerational transmission of gender preferences in educational resource allocation among children. The unique data set of Taiwan’s Panel Study of Family Dynamics project provides us a rich 3-generation education information and allows us to probe into this question. We performed our analysis along two directions: the first is to see whether the society as a whole has any macro change in gender-specific education achievement, and the second is to see whether there is any within-lineage transmission of gender preferences across generations. After carefully reviewing the education system and societal characteristics in Taiwan, we set up an empirical model to estimate and test the hypotheses of intergenerational transmission of gender preferences. We also perform various statistical analyses to support our findings, e.g. contraposition of a proposition. As far as the macro pattern is concerned, we found that although there is a clear tendency of differential treatment against females in the old generation, this tendency is significantly weakened and nearly vanishes in the young generation. Furthermore, the supporting effect of senior siblings in the old generation becomes a crowding (resource-dilution) effect in the young generation. However, within each micro lineage, there is a mild “habitus” effect in gender-specific educational resource allocation in the sense that parents who had the experience of gender-specific differential treatment tend to treat their children in a similar fashion. Moreover, this mild habitus effect is stronger for female respondents (who were the deprived group) than for male respondents (who were the privileged group).

A New Model for Family Resource Allocation Among Siblings: Competition, Forbearance, and Support

Previous research analyzing within-family education resource allocation usually employs the sibship and birth order of a child as explanatory variables. We argue in this paper that to correctly characterize the resource competition and support scenario within a family, one should identify the Sex, Seniority, and most importantly Age Difference of a child’s sibling structure, and hence we call our analysis a SSAD model of family resource allocation. We show that siblings with different combinations of SSAD may play distinct roles in family resource allocation. Ignoring such facts may distort the significance and/or direction of the prediction. We support our analysis with empirical evidence using data from Taiwan.

Clinical and parasitological response to oral chloroquine and primaquine in uncomplicated human Plasmodium knowlesi infections

Background: Plasmodium knowlesi is a cause of symptomatic and potentially fatal infections in humans. There are no studies assessing the detailed parasitological response to treatment of knowlesi malaria infections in man and whether antimalarial resistance occurs. Methods: A prospective observational study of oral chloroquine and primaquine therapy was conducted in consecutive patients admitted to Kapit Hospital, Sarawak, Malaysian Borneo with PCR-confirmed single P. knowlesi infections. These patients were given oral chloroquine for three days, and at 24 hours oral primaquine was administered for two consecutive days, primarily as a gametocidal agent. Clinical and parasitological responses were recorded at 6-hourly intervals during the first 24 hours, daily until discharge and then weekly to day 28. Vivax malaria patients were studied as a comparator group. Results: Of 96 knowlesi malaria patients who met the study criteria, 73 were recruited to an assessment of the acute response to treatment and 60 completed follow-up over 28 days. On admission, the mean parasite stage distributions were 49.5%, 41.5%, 4.0% and 5.6% for early trophozoites, late trophozoites, schizonts and gametocytes respectively. The median fever clearance time was 26.5 [inter-quartile range 16-34] hours. The mean times to 50% (PCT50) and 90% (PCT90) parasite clearance were 3.1 (95% confidence intervals [CI] 2.8-3.4) hours and 10.3 (9.4-11.4) hours. These were more rapid than in a group of 23 patients with vivax malaria 6.3 (5.3-7.8) hours and 20.9 (17.6-25.9) hours; P = 0.02). It was difficult to assess the effect of primaquine on P. knowlesi parasites, due to the rapid anti-malarial properties of chloroquine and since primaquine was administered 24 hours after chloroquine. No P. knowlesi recrudescences or re-infections were detected by PCR. Conclusions: Chloroquine plus primaqine is an inexpensive and highly effective treatment for uncomplicated knowlesi malaria infections in humans and there is no evidence of drug resistance. Further studies using alternative anti-malarial drugs, including artemisinin derivatives, would be desirable to define optimal management strategies for P. knowlesi.Publisher PDFPeer reviewe

Large Eddy Simulations (LES) and Direct Numerical Simulations (DNS) for the computational analyses of high speed reacting flows

The principal objective is to extend the boundaries within which large eddy simulations (LES) and direct numerical simulations (DNS) can be applied in computational analyses of high speed reacting flows. A summary of work accomplished during the last six months is presented

Fetal liver blood flow distribution: role in human developmental strategy to prioritize fat deposition versus brain development

Among primates, human neonates have the largest brains but also the highest proportion of body fat. If placental nutrient supply is limited, the fetus faces a dilemma: should resources be allocated to brain growth, or to fat deposition for use as a potential postnatal energy reserve? We hypothesised that resolving this dilemma operates at the level of umbilical blood distribution entering the fetal liver. In 381 uncomplicated pregnancies in third trimester, we measured blood flow perfusing the fetal liver, or bypassing it via the ductus venosus to supply the brain and heart using ultrasound techniques. Across the range of fetal growth and independent of the mother's adiposity and parity, greater liver blood flow was associated with greater offspring fat mass measured by dual-energy X-ray absorptiometry, both in the infant at birth (r = 0.43, P<0.001) and at age 4 years (r = 0.16, P = 0.02). In contrast, smaller placentas less able to meet fetal demand for essential nutrients were associated with a brain-sparing flow pattern (r = 0.17, p = 0.02). This flow pattern was also associated with a higher degree of shunting through ductus venosus (P = 0.04). We propose that humans evolved a developmental strategy to prioritize nutrient allocation for prenatal fat deposition when the supply of conditionally essential nutrients requiring hepatic inter-conversion is limited, switching resource allocation to favour the brain if the supply of essential nutrients is limited. Facilitated placental transfer mechanisms for glucose and other nutrients evolved in environments less affluent than those now prevalent in developed populations, and we propose that in circumstances of maternal adiposity and nutrient excess these mechanisms now also lead to prenatal fat deposition. Prenatal developmental influences play important roles in the human propensity to deposit fa